1. Field of the Invention
The present invention relates to a housing of an electronic apparatus such as a personal computer.
2. Description of the Related Art
A housing of an electronic apparatus is required to prevent leakage of electromagnetic wave generated by an electronic circuit inside the housing. In this case, coupling portions of a plurality of plate-shaped members of the housing must be electrically contacted.
Typically, coated plate-shaped members such as a coated steel sheet are assembled for the housing of the electronic apparatus. However, the coated section can not be electrically contacted. Therefore, in a conventional housing, in order to secure non-coated coupling portions of the plate-shaped members, when the plate-shaped member is coated, the coupling portion is masked such that the coating material is not deposited on the coupling portion. Otherwise, an uncoated member is separately prepared and is coupled to the coated coupling portion.
FIG. 1 is a perspective view showing a part of the housing of the conventional electronic apparatus, and FIG. 2 is an exploded view of the portion shown in FIG. 1. Also, FIG. 3 is a perspective showing a part of a first exterior section of the housing of the conventional electronic apparatus. As shown in FIG. 1, the housing of the conventional electronic apparatus is composed of a first exterior section 101 of a box shape and a second exterior section 102. An opening is formed in the first exterior section so as to allow the electronic apparatus to be inserted, accommodated and removed. The second exterior section 102 closes the opening of the first exterior section 101.
As shown in FIG. 3, in the first exterior section 101 of the housing of the conventional electronic apparatus, an edge portion on the attachment side of the second exterior section 102 is bent into the direction of inside of the housing to form a horizontal section 101a. The horizontal section 101a is bent downwardly to form a vertical section 101b, and then bent in a horizontal direction to form a horizontal section 101c. A plurality of grooves 103 are formed in a bent portion from which the horizontal section 101c extends in the horizontal direction, such that each of the grooves 103 is narrower at an end and wider at the other end. Also, a plurality of contact sections 105 are formed on the end edge portion of the horizontal section 101c such that the contact section 105 is located in an upper portion than the horizontal section 101c. A protrusion portion 104 for electromagnetic wave shielding is placed on a tip of each contact section 105 to have a shape of a button. The outer surface of this first exterior section 101 is coated such that a portion of the horizontal section 101c where the grooves 103 are formed is coated but a portion of the horizontal section 101c where the contact sections 105 are formed is not coated. In FIG. 3, this coated portion is hatched.
As shown in FIG. 2, a plurality of protrusion sections 106 are formed on an edge portion of the second exterior section 102 to extend downwardly such that protrusion sections 106 are inserted into the grooves 103 of the first exterior section 101. The outer surface of the second exterior section 102 is coated but the inner surface thereof is not coated.
As shown in FIG. 4, the protrusion sections 106 are inserted into the grooves 103 and then the second exterior section 102 is slid into a direction of the narrow portion of the grooves 103. Thus, the protrusion sections 106 are fitted into the grooves 103, and the second exterior section 102 is engaged with the first exterior section 101. At this time, since the protrusion 104 is protruded upwardly than the horizontal section 101c, the protrusion 104 is brought into contact with the inner surface of the second exterior section 102. Since the inner surface of the second exterior section 102 is not coated, the first and second exterior sections 101 and 102 are brought into electric contact with each other.
Also, an imaging apparatus is described in Japanese Laid Open Patent Application (JP-P2000-165713A). In this first conventional example, when a non-conductive layer is formed over an inner surface of a housing, conductive protrusions break the non-conductive layer to contact a conductive layer of the housing.
However, in the housing of the conventional electronic apparatus, when the first exterior section 101 is coated, the contact section 105 needs to be masked such that coating material is not deposited. An uncoated member is prepared and must be coupled by welding and the like. Thus, the manufacturing step and the manufacturing cost are increased. Also, in the first exterior section 101, corrosion is easily induced in the coupling portion. On the other hand, in the first conventional example, a problem of reliability that unless the conductive protrusion placed on the contact section penetrates the non-conductive layer and reaches the conductive layer, it is not brought into the electrical contact.
In conjunction with the above description, a plastic cover is described in Japanese Laid Open Patent Application (JP-A-Heisei 1-204499). In this conventional example, an electronic apparatus has a plastic cover on which an electric conductive film is coated and grounded. A terminal with a hole is fixed to a protrusion provided on a surface to be coated. The electric conductive film is coated on the surface including the terminal. The terminal is connected to a ground potential member of the apparatus by a wire.